High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. Cockpit noise in a jet aircraft is mostly due to airflow at hundreds of miles per hour. This 3 × 3 contingency table shows 61 observations of data collected by an airline pilot using a handheld sound meter in a certain aircraft cockpit. Noise level is defined as "low" (under 88 decibels), "medium" (88 to 91 decibels), or "high" (92 decibels or more). There are three flight phases (climb, cruise, descent).

Cockpit NoiseFlight PhaseNoise LevelClimb (B)Cruise (C)Descent (D)Row TotalLow (L)62614Medium (M)183829High (H)131418Column Total2582861

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(a)Calculate the following probabilities:(Round your answers to 4 decimal places.)

i.P(B)ii.P(L)iii.P(H|C)iv.P(H|D)v.P(LandB)vi.P(LandC)

(b)Do you see evidence that noise level depends on flight phase?

multiple choice

• Yes
• No